REPTILES OF MASSACHUSETTS. 233 



CROTALUS. Lin. 



Generic characters. Head large, triangular, rounded in 

 front, covered with plates anteriorly ; vertex and occiput with 

 scales ; a deep pit between the eye and nostril ; upper jaw 

 armed with poisonous fangs ; body elongated, thick ; tail short 

 and thick, terminating in a rattle, which is a corneous produc- 

 tion of the epidermis ; plates on the abdomen, and under the 

 tail. 



C. durissus. Kalm. The banded Rattle Snake. 



Turton's Linnaeus, vol. i. p. 672. 



Shaw's Gen. Zoology, vol. iii. pt. 2. p. 317, et fig. 



Harlan's Med. and Phys. Res. p. 132. 



N. A. Herpetol. vol. iii. p. 81. 



This species, which is generally known in New England as 

 the rattle snake, is extensively distributed throughout the 

 State. Two fine specimens, taken at Douglas the last sum- 

 mer, gave me an opportunity for minute observation. One of 

 them measured three feet and one inch in length, and was five 

 inches in circumference ,* the other was three feet long. From 

 the former, I drew up the following notes : 



Upper part of the body, of a yellowish brown color, with 

 rhomboidal black spots continued along the back, margined 

 with bright yellow ; upon each side of these rhombs a black 

 band is continued to the sides of the body, where it terminates 

 in an irregularly quadrate black spot ; tail black. Body, be- 

 neath, yellow, with fuliginous dots and blotches distributed 

 irregularly over its surface. Scales on the back elongated, 

 carinated ; scales upon the sides larger, carinse less prominent. 

 Length of the head, one inch and a half ; width of the head, 

 one inch. Top of the head, flattened ; scales upon the top, 

 small on the sides of the head, large, pentagonal ; on the 

 edges of the jaws, quadrangular. Snout, terminated by one 

 large plate ; a quadrangular plate on each side of this j directly 

 back of these, a smaller one, in which are the circular 

 nostrils, situated obliquely, pointing forwards. Directly 

 30 



